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Abstract:

A wireless communication system according to the present invention
includes a wireless communication terminal and a base station apparatus.
The base station apparatus transmits to the wireless communication
terminal, cell information relating to a cell of the base station
apparatus, and selectability information indicating whether the cell
information is manually selectable. The wireless communication terminal
receives from the base station apparatus the cell information and the
selectability information of the base station apparatus.

Claims:

1. A wireless communication system comprising a wireless communication
terminal and a base station apparatus, wherein said base station
apparatus transmits to said wireless communication terminal, cell
information relating to a cell of said base station apparatus, and
selectability information indicating whether the cell information is
manually selectable, and said wireless communication terminal receives
from said base station apparatus the cell information and the
selectability information of said base station apparatus.

2. The wireless communication system according to claim 1, wherein said
base station apparatus sets for System Information the cell information
and the selectability information of said base station apparatus, and
informs a cell of said base station apparatus of the System Information.

3. The wireless communication system according to claim 1, wherein said
base station apparatus sets for a predetermined message the cell
information and the selectability information of said base station
apparatus, and transmits the predetermined message to said wireless
communication terminal.

4. The wireless communication system according to claim 1, wherein said
base station apparatus determines whether the cell information of said
base station apparatus is manually selectable depending on a
communication status of said base station apparatus.

5. The wireless communication system according to claim 1, wherein said
base station apparatus determines whether the cell information of said
base station apparatus is manually selectable depending on an indication
entered into said base station apparatus.

6. The wireless communication system according to claim 1, wherein said
base station apparatus determines whether the cell information of said
base station apparatus is manually selectable depending on a current time
period.

7. The wireless communication system according to claim 1, wherein said
wireless communication terminal holds in advance, a permitted list that
is a list of cell information of cells to which the terminal itself can
connect, and based on the permitted list and the selectability
information, determines whether the cell information of said base station
apparatus is set as a candidate for manual selection.

8. The wireless communication system according to claim 7, wherein from
among cell information of neighboring cells, said wireless communication
terminal removes from candidates for manual selection, cell information
that is not included in the permitted list and for which the
selectability information indicates manually non-selectable.

9. The wireless communication system according to claim 7, wherein from
among cell information of neighboring cells, said wireless communication
terminal registers in a restricted list, cell information that is not
included in the permitted list and for which the selectability
information indicates manually non-selectable, and registers in a list of
candidates for selection, cell information of other neighboring cells,
and from among cell information of neighboring cells included in the
restricted list, removes from candidates for manual selection, cell
information that is not included in the list of candidates for selection.

10. The wireless communication system according to claim 9, wherein when
selecting a cell having manually selected cell information, said wireless
communication terminal removes a cell having cell information for which
the selectability information indicates manually non-selectable, and
selects a cell having cell information for which the selectability
information indicates manually selectable or a cell for which no
selectability information is set.

11. The wireless communication system according to claim 8, wherein when
a candidate for manual selection of the cell information is displayed,
said wireless communication terminal does not display cell information
removed from the candidates for manual selection or displays the cell
information as non-selectable.

12. The wireless communication system according to claim 7, wherein said
base station apparatus determines whether the cell information of said
base station apparatus is manually selectable for each access class of
said wireless communication terminal, and transmits to said wireless
communication terminal, the selectability information for each access
class, and said wireless communication terminal determines whether the
cell information of said base station apparatus is set as a candidate for
manual selection based on the selectability information for the access
class assigned to the terminal itself in advance.

13. A base station apparatus that performs wireless communication with a
wireless communication terminal, comprising a transmitter that transmits
to said wireless communication terminal, cell information relating to a
cell of said base station apparatus, and selectability information
indicating whether the cell information is manually selectable.

14. The base station apparatus according to claim 13, further comprising
a controller that sets for System Information, the cell information and
the selectability information of said base station apparatus, wherein
said transmitter informs a cell of said base station apparatus of the
System Information.

15. The base station apparatus according to claim 13, further comprising
a controller that sets for a predetermined message the cell information
and the selectability information of said base station apparatus, wherein
said transmitter transmits the predetermined message to said wireless
communication terminal.

16. The base station apparatus according to claim 14, wherein said
controller determines whether the cell information of said base station
apparatus is manually selectable depending on a communication status of
said base station apparatus.

17. The base station apparatus according to claim 14, wherein said
controller determines whether the cell information of said base station
apparatus is manually selectable depending on an indication entered into
said base station apparatus.

18. The base station apparatus according to claim 14, wherein said
controller determines whether the cell information of said base station
apparatus is manually selectable depending on a current time period.

19. The base station apparatus according to claim 14, wherein said
controller determines whether the cell information of said base station
apparatus is manually selectable for each access class of said wireless
communication terminal, and said transmitter transmits to said wireless
communication terminal, the selectability information for each access
class.

20. A wireless communication terminal that performs wireless
communication with a base station apparatus, comprising a receiver that
receives from said base station apparatus, cell information relating to a
cell of said base station apparatus, and selectability information
indicating whether the cell information is manually selectable.

21. The wireless communication terminal according to claim 20, further
comprising a controller that holds in advance, a permitted list that is a
list of cell information of cells to which the terminal itself can
connect, and based on the permitted list and the selectability
information, determines whether the cell information of said base station
apparatus is set as a candidate for manual selection.

22. The wireless communication terminal according to claim 21, wherein,
from among cell information of neighboring cells, said controller removes
from candidates for manual selection, cell information that is not
included in the permitted list and for which the selectability
information indicates manually non-selectable.

23. The wireless communication terminal according to claim 21, wherein
from among cell information of neighboring cells, said controller
registers in a restricted list, cell information that is not included in
the permitted list and for which the selectability information indicates
manually non-selectable, and registers in a list of candidates for
selection, cell information of other neighboring cells, and from among
cell information of neighboring cells included in the restricted list,
removes from candidates for manual selection, cell information that is
not included in the list of candidates for selection.

24. The wireless communication terminal according to claim 23, wherein
when selecting a cell having manually selected cell information, said
controller removes a cell having cell information for which the
selectability information indicates manually non-selectable, and selects
a cell having cell information for which the selectability information
indicates manually selectable or a cell for which no selectability
information is set.

25. The wireless communication terminal according to claim 22, wherein
when a candidate for manual selection of the cell information is
displayed, said controller does not display cell information that has
been removed from the candidates for manual selection or displays the
cell information as non-selectable.

26. The wireless communication terminal according to claim 20, wherein
said receiver receives the selectability information for each access
class, and said controller determines whether the cell information of
said base station apparatus is set as a candidate for manual selection
based on the selectability information for the access class assigned to
the terminal itself in advance.

27. A wireless communication method which is performed by a wireless
communication system including a wireless communication terminal and a
base station apparatus, comprising the steps of: said base station
apparatus transmitting to said wireless communication terminal, cell
information relating to a cell of said base station apparatus, and
selectability information indicating whether the cell information is
manually selectable, and said wireless communication terminal receiving
from said base station apparatus the cell information and the
selectability information of said base station apparatus.

28. A wireless communication method which is performed by a base station
apparatus that performs wireless communication with a wireless
communication terminal, comprising the step of: transmitting to said
wireless communication terminal, cell information relating to a cell of
said base station apparatus, and selectability information indicating
whether the cell information is manually selectable.

29. A wireless communication method that is performed by a wireless
communication terminal that performs wireless communication with a base
station apparatus, comprising the step of: receiving from said base
station apparatus, cell information relating to a cell of said base
station apparatus, and selectability information indicating whether the
cell information is manually selectable.

Description:

TECHNICAL FIELD

[0001] The present invention relates to a wireless communication system, a
base station apparatus, a wireless communication terminal and a wireless
communication method.

BACKGROUND ART

[0002] Some recent wireless communication systems include, as a base
station apparatus, a small wireless base station which is called a femto
base station (Home NB or Home eNB: hereinafter referred to an H(e)NB when
indicating both of them).

[0003] The femtocell that is an area where wireless communication is
possible, which is built by an H(e)NB, is assigned a CSG ID (3GPP
TS25.331) of a Closed Subscriber Group (hereinafter referred to as CSG).
And only UE (User Equipment) that is a wireless communication terminal
used by a user who subscribes to the CSG can connect to the femtocell
(3GPP TS25.304).

[0004] Further, the UE used by the user subscribing to the CSG holds
therein an Allowed CSG List that is a list of CSG IDs that are assigned
to connectable femtocells to manage connectable femtocells (3GPP
TS25.304).

[0005] Meanwhile, a user who does not subscribe to the CSG can also select
a femtocell assigned a CSG ID that is not present in the Allowed CSG List
by Manual CSG ID Selection (3GPP TS25.304) and make a connection request
from his/her UE.

[0006] In this case, even though services that can be used at the
beginning of the connection are limited, the UE that made a connection
request can add to the Allowed CSG List the CSG ID that is manually
selected when a connection is successfully established by the
communication with a Core Network Node (3GPP TS25.304).

[0007] Incidentally, when an H(e)NB is set up in a heavily populated area
such as a shopping center and a live performance club, the CSG ID
assigned to the femtocell built by the H(e)NB is included in the Allowed
CSG List such that the UE used by the owner having the H(e)NB and the
concerned parties thereof are allowed to connect to the femtocell.

[0008] However, in this case, even though the CSG ID of the femtocell is
not included in the Allowed CSG List, the UE of the general user other
than the owner of the H(e)NB and the concerned parties thereof is also
sometimes allowed to make a connection request to the femtocell by Manual
CSG ID Selection.

[0009] It is, therefore, expected that a considerable number of UEs of
general user repeatedly make a connection request to the femtocell; at
that time, a problem in which signaling congestion occurs at the H(e)NB,
which prevents the UE from being used by the owner of the H(e)NB and the
concerned parties thereof from making a connection request, is expected
to arise.

[0010] In particular, it is considered that, when the H(e)NB operates in a
Hybrid Access Mode, the above problem is more likely to occur. The Hybrid
Access Mode means a mode that includes, as UEs that are connectable to a
femtocell built by an H(e)NB, not only UEs that are CSG members
subscribing to the CSG but also UEs that are non-CSG members (TS22.220
Ver9.0.0).

[0011] In order to solve the above problem, building a framework in which
a connection request to a femtocell from UE of a CSG member is allowed
and in which a connection request to the femtocell from UE of a non-CSG
member is restricted can be conceived.

[0012] For example, the disclosure document 3GPP: RP-090307 proposes a
parameter (Cell Reserved for CSG) allowing a connection request from only
UEs which have the CSG ID of the femtocell included in the Allowed CSG
List. Using this parameter, the following may be achieved:

(1) Prohibit connection requests to a femtocell from all UEs (existing).
(2) Allow connection requests to the femtocell only from UEs which have
the CSG ID of the femtocell included in the Allowed CSG List, and
prohibit connection requests from other UEs (new).

[0015] Incidentally, in the configuration in which the above parameter:
CSG Reserved for CSG is used, connection requests to a femtocell from all
UEs other than UEs which have the CSG ID of the femtocell included in the
Allowed CSG List, that is to say, not only UEs having no CSG ID of the
femtocell included in the Allowed CSG List, but also UEs not supporting
the CSG are not allowed.

[0016] Therefore, when utilizing a femtocell, a user who uses an old UE
not supporting the CSG has to forcibly buy a new one that supports the
CSG.

[0017] Accordingly, in order to allow a connection request to a femtocell
from UE not supporting a CSG while preventing signaling congestion from
occurring at an H(e)NB, it is considered that a framework that prohibits
the UE from manually selecting the CSG ID of the femtocell built by the
H(e)NB is needed.

[0018] However, in the present configuration, there is a problem in which
since UE cannot know whether the CSG ID of the femtocell is manually
selectable, it is impossible to prohibit the UE from manually selecting
the CSG ID.

[0019] Thus, it is an object of the present invention to provide a
wireless communication system, a base station apparatus, a wireless
communication terminal and a communication method by which UE can know
whether the CSG ID of a femtocell is manually selectable.

Means that Solve the Problem

[0020] A wireless communication system according to the present invention
includes

[0021] a wireless communication terminal and a base station apparatus,
wherein

[0022] the base station apparatus

[0023] transmits to the wireless communication terminal, cell information
relating to a cell of the base station apparatus, and selectability
information indicating whether the cell information is manually
selectable, and

[0024] the wireless communication terminal

[0025] receives from the base station apparatus the cell information and
the selectability information of the base station apparatus.

[0026] The base station apparatus of the present invention

[0027] which performs wireless communication with the wireless
communication terminal, includes

[0028] a transmitter that transmits to the wireless communication
terminal, cell information relating to a cell of the base station
apparatus, and selectability information indicating whether the cell
information is manually selectable.

[0029] The wireless communication terminal of the present invention

[0030] which performs wireless communication with a base station
apparatus, includes

[0031] a receiver that receives from the base station apparatus, cell
information relating to a cell of the base station apparatus, and
selectability information indicating whether the cell information is
manually selectable.

[0032] A first wireless communication method of the present invention

[0033] which is performed by a wireless communication system including a
wireless communication terminal and a base station apparatus, includes
the steps of:

[0034] the base station apparatus transmitting to the wireless
communication terminal, cell information relating to a cell of the base
station apparatus, and selectability information indicating whether the
cell information is manually selectable, and

[0035] the wireless communication terminal receiving from the base station
apparatus the cell information and the selectability information of the
base station apparatus.

[0036] A second wireless communication method of the present invention

[0037] which is performed by a base station apparatus that performs
wireless communication with the wireless communication terminal, includes
the step of

[0038] transmitting to the wireless communication terminal, cell
information relating to a cell of the base station apparatus, and
selectability information indicating whether the cell information is
manually selectable.

[0039] A third wireless communication method of the present invention

[0040] which is performed by a wireless communication terminal that
performs wireless communication with the base station apparatus, includes
the step of:

[0041] receiving from the base station apparatus, cell information
relating to a cell of the base station apparatus, and selectability
information indicating whether the cell information is manually
selectable.

Advantageous Effect of Invention

[0042] As described above, in the present invention, a base station
apparatus transmits to a wireless communication terminal, cell
information relating to a cell of the base station apparatus, and
selectability information indicating whether the cell information is
manually selectable.

[0043] Therefore, an effect is obtained in which the wireless
communication terminal can know whether cell information of the base
station apparatus is manually selectable in the wireless communication
terminal.

BRIEF DESCRIPTION OF DRAWINGS

[0044] FIG. 1 is a block diagram showing a configuration of a wireless
communication system according to a first exemplary embodiment of the
present invention.

[0045] FIG. 2 is a sequence diagram illustrating the operation of the
wireless communication system according to the first exemplary embodiment
of the present invention.

[0046] FIG. 3 is a diagram showing a network configuration of a wireless
communication system according to a second exemplary embodiment of the
present invention.

[0047] FIG. 4 is a diagram showing a parameter: Cell Prohibited for Manual
CSG ID Selection that is set for System Information by an H(e)NB
according to the second exemplary embodiment of the present invention.

[0048] FIG. 5 is a block diagram showing a configuration of the H(e)NB
according to the second exemplary embodiment of the present invention.

[0049] FIG. 6 is a block diagram showing a configuration of UE according
to the second exemplary embodiment of the present invention.

[0050] FIG. 7 is a sequence diagram illustrating the operation of the
wireless communication system according to the second exemplary
embodiment of the present invention.

[0051] FIG. 8 is a flowchart illustrating the operation of the H(e)NB
according to the second exemplary embodiment of the present invention.

[0052] FIG. 9 is a flowchart illustrating the operation of the UE
according to the second exemplary embodiment of the present invention.

[0053] FIG. 10 is a diagram showing a display screen of candidates for
manual CSG ID Selection that is displayed on the UE according to the
second exemplary embodiment of the present invention.

[0054] FIG. 11 is a sequence diagram illustrating the operation of a
wireless communication system according to a third exemplary embodiment
of the present invention.

[0055] FIG. 12A is a flowchart illustrating the operation of UE according
to the third exemplary embodiment of the present invention.

[0056] FIG. 12B is a flowchart illustrating the procedure for extracting a
candidate for manual CSG ID Selection by the UE according to the third
exemplary embodiment of the present invention.

[0057] FIG. 13 is a diagram showing a parameter: Access Class Barred for
Manual CSG ID Selection that is set for System Information by an H(e)NB
according to a fourth exemplary embodiment of the present invention.

[0058] FIG. 14 is a diagram showing a network configuration of a wireless
communication system according to a fifth exemplary embodiment of the
present invention.

DESCRIPTION OF EMBODIMENTS

[0059] Exemplary embodiments of the present invention will now be
described with reference to the drawings.

First Exemplary Embodiment

[0060] Referring to FIG. 1, a wireless communication system of the present
exemplary embodiment includes H(e)NB 101 that is a base station apparatus
and UE 401 that is a wireless communication terminal. Note that for the
sake of simplification, although only one H(e)NB and one UE are shown in
FIG. 1, the number of H(e)NBs and UEs are not limited thereto.

[0061] H(e)NB 101 includes a transmitter 1000 that transmits to UE 401,
cell information relating to a femtocell built by H(e)NB 101 and
selectability information indicating whether the cell information is
manually selectable by UE 401.

[0062] Note that cell information is information for identifying a cell or
indicating a cell attribute, such as a CSG ID.

[0063] In addition, UE 401 includes receiver 4000 that receives from
H(e)NB 101, the cell information of H(e)NB 101 and selectability
information.

[0064] The operation of the wireless communication system according to the
present exemplary embodiment will now be described with reference to a
sequence diagram shown in FIG. 2.

[0065] In step A1, transmitter 1000 of H(e)NB 101 transmits to UE 401 the
cell information of H(e)NB 101 and the selectability information of the
cell information. However, the cell information and selectability
information do not necessarily have to be transmitted at the same time;
they may be transmitted separately. The cell information and
selectability information are received at receiver 4000 of UE 401.

[0066] Therefore, the present exemplary embodiment produces an effect in
which UE 401 can know whether the cell information of H(e)NB 101 is
manually selectable by UE 401.

Second Exemplary Embodiment

[0067] The present exemplary embodiment is a concrete example of the
configuration and operation of the first exemplary embodiment.

[0068] FIG. 3 shows a network configuration of a wireless communication
system according to the present exemplary embodiment.

[0069] Referring to FIG. 3, a wireless communication system of the present
exemplary embodiment includes H(e)NBs 101 and 102 that are base station
apparatuses and UE 401 that is a wireless communication terminal. Note
that for the sake of simplification, although two H(e)NBs and one UE are
shown in FIG. 3, the number of H(e)NBs and UEs are not limited thereto.
Further, although the UE is present in the range of two femtocells, UE
may be present in the range of one femtocell or three or more femtocells.

[0070] H(e)NB 101 builds femtocell 201 that has been assigned CSG ID 301
that is cell information, and informs femtocell 201 of System Information
for which CSG ID 301 is set. At that time, H(e)NB 101 also sets for
System Information a parameter that is selectability information
indicating whether CSG ID 301 is manually selectable. In this
specification, this parameter is set for System Information as Cell
Prohibited for Manual CSG ID Selection as shown in FIG. 4.

[0071] H(e)NB 102 builds femtocell 202 that has been assigned CSG ID 302
that is cell information, and informs femtocell 202 of System Information
for which CSG ID 302 is set. At that time, H(e)NB 102 also sets for
System information a parameter: Cell Prohibited for Manual CSG ID
Selection that is selectability information indicating whether CSG ID 302
is manually selectable.

[0072] UE 401 is present in the range of both femtocells 201 and 202, can
acquire System Information that has been informed to each of femtocells
201 and 202, and recognizes the parameter: Cell Prohibited for Manual CSG
ID Selection indicating whether each of CSG IDs 301 and 302 is manually
selectable.

[0073] FIG. 5 shows a detailed configuration of H(e)NB 101. Note that
H(e)NB 102 has the same configuration as that of H(e)NB 101.

[0077] Load controller 1005 knows the rate of signaling processing
completion, the rate of transmission power utilization, the rate of
network resource utilization and the like in femtocell 201 built by
H(e)NB 101, and based on these, assesses the load state of H(e)NB 101.

[0078] Then, based on the load state of H(e)NB 101, load controller 1005
determines whether UE that is present in the range of femtocell 201 can
manually select CSG ID 301 that is registered in CSG ID storage memory
1004, and if the load state is low, sets the parameter: Cell Prohibited
for Manual CSG ID Selection to "permitted (Not Prohibited, Not Barred,
Reserved)", which means manually selectable, on the other hand, if the
load state is high, to "restricted (Prohibited, Barred, Not Reserved)",
which means manually non-selectable.

[0079] System Information setting unit 1003 sets for System Information
the parameter: Cell Prohibited for Manual CSG ID Selection that is
acquired from load controller 1005, and CSG ID 301 that is acquired from
CSG ID storage memory 1004.

[0080] Transmission processing unit 1002 broadcasts System Information
that is acquired from System Information setting unit 1003 to femtocell
201 through transmitting and receiving antenna 1001.

[0084] Reception processing unit 4003 receives System Information that has
been informed to femtocell 201 and femtocell 202 through transmitting and
receiving antenna 4001, and registers System Information in neighboring
cell list storage memory 4006.

[0085] Cell selection processing unit 4004 compares the CSG ID of a
neighboring cell included in neighboring cell list storage memory 4006
with CSG IDs included in Allowed CSG List storage memory 4005, and sets
as a candidate for manual CSG ID Selection, the CSG ID that is a
neighboring cell CSG ID and is included in Allowed CSG List storage
memory 4005.

[0086] In addition, cell selection processing unit 4004 recognizes the
value of the parameter: Cell Prohibited for Manual CSG ID Selection,
which is a parameter of the CSG ID for each neighboring cell included in
neighboring cell list storage memory 4006, and also sets as a candidate
for manual CSG ID Selection, a CSG ID that is a neighboring cell CSG ID
and for which the value of the parameter: Cell Prohibited for Manual CSG
ID Selection is "permitted".

[0087] Cell selection processing unit 4004 displays on display 4007 the
list of candidates for manual CSG ID Selection so that a user using UE
401 can manually select at least one CSG ID from among CSG IDs displayed
on display 4007 as candidates for manual selection.

[0088] In addition, cell selection processing unit 4004 determines, as the
destination of the connection request, the femtocell that has been
assigned the CSG ID that is manually selected by the user.

[0089] Transmission processing unit 4002 generates a connection request
message, and transmits the connection request message through
transmitting and receiving antenna 4001 to the H(e)NB building the
femtocell that has been assigned the CSG ID that is manually selected by
the user.

[0090] Although the configuration of the present exemplary embodiment has
been described in detail, the configuration of the wireless communication
system shown in FIG. 3, the configuration of the H(e)NB shown in FIG. 5
and the configuration of the UE shown in FIG. 6 are all well known by
those skilled in the art engaged in wireless communication systems
complying with 3GPP except for the portion relating to the parameter:
Cell Prohibited for Manual CSG ID Selection, and are not related to the
present invention directly; therefore, description of the detailed
configuration will be omitted.

[0091] The operation of the wireless communication system according to the
present exemplary embodiment will now be described.

[0092] First, the entire operation of the wireless communication system of
the present exemplary embodiment will be described with reference to the
sequence diagram shown in FIG. 7.

[0093] Referring to FIG. 7, in step B1, H(e)NB 101 determines the value of
the parameter: Cell Prohibited for Manual CSG ID Selection, and then, in
step B2, informs femtocell 201 of System Information for which CSG ID 301
and the parameter: Cell Prohibited for Manual CSG ID Selection have been
set.

[0094] Meanwhile, in step B3, H(e)NB 102 determines the value of the
parameter: Cell Prohibited for Manual CSG ID Selection, and then, in step
B4, informs femtocell 202 of System Information for which CSG ID 302 and
the parameter: Cell Prohibited for Manual CSG ID Selection have been set.

[0096] Next, the operation of H(e)NBs 101 and 102 will be described. Here,
the operation of H(e)NB 101 will be described with reference to the
flowchart shown in FIG. 8.

[0097] Referring to FIG. 8, first, in step C1, load controller 1005
assesses the load state of H(e)NB 101 based on the rate of signaling
processing completion, the rate of transmission power utilization, the
rate of network resource utilization and the like in femtocell 201 built
by H(e)NB 101.

[0098] If H(e)NB 101 is in a high load state, in step C2, load controller
1005 sets the value of the parameter: Cell Prohibited for Manual CSG ID
Selection to [restricted]; on the other hand, if H(e)NB 101 is in a low
load state, in step C3, load controller 1005 sets the value of the
parameter: Cell Prohibited for Manual CSG ID Selection to [allowed].

[0099] Note that as the method of assessing a high load state or a low
load state, for example, a method may be considered in which a high load
is assessed when a predetermined threshold is exceeded in a predetermined
number of items or more from among the items including the rate of
signaling processing completion, the rate of transmission power
utilization, the rate of network resource utilization and the like, and
otherwise a low load is assessed, without being limited to this.

[0101] Note that in the present exemplary embodiment, although the
assessment of the load state of H(e)NB 101 is performed by H(e)NB 101
itself, it may be performed at the higher node not shown (Core Network
Node and H(e)NB GW).

[0102] In this case, the higher node may notify the assessment result of
the load state of H(e)NB 101, and H(e)NB 101 may set the value of the
parameter based on the notified assessment result. Alternatively, the
higher node may make a setting request of the value of the parameter
based on the assessment result of the load state of H(e)NB 101, and
H(e)NB 101 may set the value of the parameter based on the notified
setting request. Note that the higher node notifies H(e)NB 101 of a
message including an assessment result indicating that H(e)NB 101 is in a
high load state and a modification request indicating that the value of
the parameter is to be set to [restricted] since H(e)NB 101 is in a high
load state. In addition, H(e)NB 101 may receive the message that is
transmitted by the higher node itself when it is in a high load state, so
as to set the value of the parameter to [restricted]. The message
includes RANAP: Overload message, for example.

[0103] In addition, in the present exemplary embodiment, although toad
states such as the rate of signaling processing completion, the rate of
transmission power utilization, the rate of network resource utilization
and the like are used as an indices indicating the communication
situation of H(e)NB 101, for example, in the femtocell 201 of H(e)NB 101,
the number of UEs within range, the number of UEs in communication, the
number of voice calls in communication, the number of packet calls in
communication, the number of HSDPA users, the number of HSUPA users, the
number of MBMS users, the number of channelization codes used, the number
of active wireless access bearers, the rate of H(e)NB 101 CPU usage, the
rate of H(e)NB 101 memory usage, the rate of communication completion,
the rate of call loss, the rate of connection success/failure, the
frequency of handover, the rate of handover success/failure, the amount
of uplink interference, the amount of downlink interference, the amount
of uplink buffer, the amount of downlink buffer and the like may be used.

[0104] In addition, although the present exemplary embodiment determines
the value of the parameter depending on the communication situation of
H(e)NB 101, the value of the parameter may be determined depending on the
current time period. It can be considered that, for example, in the
middle of the night and in the time period during which the owner of
H(e)NB 101 and the concerned parties thereof are in conference, the
parameter is set to [allowed].

[0105] Alternatively, the value of the parameter may be determined
depending on the indication entered into H(e)NB 101 by an operator. In
addition, the indication may be entered into H(e)NB 101 by remote control
operation from a specific UE such as the UE of the owner of H(e)NB 101
and the concerned parties thereof.

[0106] In addition, in the present exemplary embodiment, [allowed] may be
the same thing that as not setting the parameter described above in
System Information.

[0107] In addition, in the present exemplary embodiment, while the
parameter: Cell Prohibited for Manual CSG ID Selection is a separate,
individual parameter, it may be a value which is the part of the existing
parameters.

[0108] Next, the operation of UE 401 will be described with reference to
the flowchart shown in FIG. 9.

[0109] Referring to FIG. 9, first, in step D1, reception processing unit
4003 receives System Information of the neighboring cell to acquire the
CSG ID of the neighboring cell.

[0111] If the CSG ID of the neighboring cell is included in the Allowed
CSG List, in step D3, cell selection processing unit 4004 displays on
display 4007, an indication that the CSG ID of the neighboring cell is
included in the Allowed CSG List, and in step D4, sets the CSG ID of the
neighboring cell as a candidate for manual selection.

[0112] Meanwhile, if the CSG ID of the neighboring cell is not included in
the Allowed CSG List, in step D5, cell selection processing unit 4004
recognizes the value of the parameter: Cell Prohibited for Manual CSG ID
Selection that is set for System Information that has been informed to
the neighboring cell. If [allowed] is set or no parameter is set, in step
D4, cell selection processing unit 4004 keeps the CSG ID of the
neighboring cell as a candidate for manual selection, and if [restricted]
is set, in step D6, cell selection processing unit 4004 removes the CSG
ID of the neighboring cell from the candidates for manual selection.

[0113] Thereafter, in step D7, cell selection processing unit 4004
displays on display 4007 the list of candidates for manual CSG ID
Selection. Note that the CSG ID that has been removed from the candidates
for manual selection may not be displayed, or may be displayed as a
non-selectable CSG ID.

[0114] An example of the display screen at display 4007 in this time is
shown in FIG. 10.

[0115] Namely, the CSG ID that satisfies either (A) or (B) is set as a
candidate for manual selection, and the user who uses UE 401 can manually
select at least one CSG ID from among candidates for manual CSG ID
Selection.

(A) CSG ID that is included in Allowed CSG List (B) CSG ID for which the
value of the parameter: Cell Prohibited for Manual CSG ID Selection of
System Information is set to [allowed]

[0116] In other words, the user who uses UE 401 cannot manually select the
CSG ID that is not included in the Allowed CSG List, and for which the
value of the parameter: Cell Prohibited for Manual CSG ID Selection of
System Information of the femtocell assigned the CSG ID is set to
[restricted].

[0117] In the example in FIG. 10, since CSG IDs [301, 304, 305] are
included in the Allowed CSG List of UE 401, they are set as candidates
for manual CSG ID Selection.

[0118] In particular, CSG ID [305] becomes a candidate for manual CSG ID
Selection since it is included in the Allowed CSG List of UE 401 even
through the value of the parameter: Cell Prohibited for Manual CSG ID
Selection of System Information of the femtocell is [restricted]. This is
due to the fact, for example, that the owner of the H(e)NB that builds
the femtocell of CSG ID [305] or the concerned parties thereof have CSG
ID [305] included in the Allowed CSG List of UEs, and are requested to
allow a connection request to the femto cell of CSG ID [305] from UE,
even if the femtocell of CSG ID [305] is in a crowded situation.

[0119] In addition, although CSG IDs [306, 307] are not included in the
Allowed CSG List, they are set as candidates for manual CSG ID Selection
since the value of the'parameter: Cell Prohibited for Manual CSG ID
Selection of System Information of the femtocell is set to [allowed].

[0120] In addition, since CSG IDs [302, 303] are not included in the
Allowed CSG List, and the value of the parameter: Cell Prohibited for
Manual CSG ID Selection of System Information of the femtocell is set to
[restricted], they are removed from candidates for manual CSG ID
Selection.

[0121] As described above, in the exemplary embodiment, the value of the
parameter: Cell Prohibited for Manual CSG ID Selection that indicates
whether each of H(e)NBs 101 and 102 can manually select CSG IDs 301 and
302 that has been assigned to femtocells 201 and 202 is set in System
Information that is informed to femtocells 201 and 202.

[0122] Therefore, an effect can be obtained in which UE 401 can know
whether CSG IDs 301 and 302 can be manually selected by the user.

[0123] In addition, in the present exemplary embodiment, UE 401 removes a
CSG ID that is not included in the Allowed CSG List and for which the
parameter: Cell Prohibited for Manual CSG ID Selection is set to
[restricted] from candidates for manual CSG ID Selection.

[0124] Therefore, making a connection request to the femtocell by the UE
of general user other than the owner of the H(e)NB and the concerned
parties thereof can be reduced, thus an effect can be obtained in which
the occurrence of signaling congestion at the H(e)NB can be reduced.

[0125] In addition, in the present exemplary embodiment, since a specific
CSG ID is simply removed from the candidates for manual selection, an
effect can be obtained in which not only a connection request to the
femtocell by the UE in which CSG ID is included in the Allowed CSG List
can be allowed, but also a connection request to the femtocell by an old
UE not supporting CSG and by UE in which CSG ID is not included in the
Allowed CSG List can also be allowed.

Third Exemplary Embodiment

[0126] Compared to the second exemplary embodiment of FIG. 3, the present
exemplary embodiment has the same network configuration of the wireless
communication system, but the same CSG ID 301 is assigned to both
femtocells 201 and 202, thus the operation thereof is different from that
of the second exemplary embodiment.

[0127] First, the entire operation of the wireless communication system of
the present exemplary embodiment will be described with reference to the
sequence diagram shown in FIG. 11.

[0128] Referring to FIG. 11, in step E1, H(e)NB 101 determines the value
of the parameter: Cell Prohibited for Manual CSG ID Selection to be
[restricted], and then, in step E2, informs femtocell 201 of System
Information for which CSG ID 301 and the parameter: Cell Prohibited for
Manual CSG ID Selection have been set.

[0129] Meanwhile, in step E3, H(e)NB 102 determines the value of the
parameter: Cell Prohibited for Manual CSG ID Selection to be [allowed],
and then, in step E4, informs femtocell 202 of System Information for
which CSG ID 301 and the parameter: Cell Prohibited for Manual CSG ID
Selection have been set.

[0131] Namely, in FIG. 11, the parameter: Cell Prohibited for Manual CSG
ID Selection of System Information of femtocell 201 assigned CSG ID 301
is set to [restricted], and the parameter: Cell Prohibited for Manual CSG
ID Selection of System Information of another femtocell 202 assigned the
same CSG ID 301 is set to [allowed].

[0132] In the first exemplary embodiment, UE 401 removes from candidates
for manual selection, the CSG ID for which the parameter: Cell Prohibited
for Manual CSG ID Selection is [restricted].

[0133] On the contrary, in the present exemplary embodiment, since both
femtocells 201 and 202 set the same CSG ID 301 for System Information,
there is a possibility, as shown in FIG. 11, that even if the parameter:
Cell Prohibited for Manual CSG ID Selection of one femtocell 201 is set
to [restricted], the parameter: Cell Prohibited for Manual CSG ID
Selection of the other femtocell 202 is set to [allowed].

[0134] In this case, in UE 401 that is present in the range of two
femtocells 201 and 202, CSG ID 301 should not be removed from candidates
for manual selection, and CSG ID 301 should be kept as a candidates for
manual selection so that femtocell 202 becomes selectable.

[0135] Thus, in the present exemplary embodiment, the operation of UE 401
is further devised. The operation of UE 401 will be described with
reference to the flowchart shown in FIG. 12A.

[0136] Referring to FIG. 12A, first, in step F1, reception processing unit
4003 receives System Information of the neighboring cell to acquire the
CSG ID of the neighboring cell.

[0138] If the CSG ID of the neighboring cell is included in the Allowed
CSG List, in step F3, cell selection processing unit 4004 displays on
display 4007 an indication that the CSG ID of the neighboring cell is
included in the Allowed CSG List, and in step F4, adds the CSG ID of the
neighboring cell to the list of candidates for selection.

[0139] Meanwhile, if the CSG ID of the neighboring cell is not included in
the Allowed CSG List, in step F5, cell selection processing unit 4004
recognizes the value of the parameter: Cell Prohibited for Manual CSG ID
Selection that is set for System Information that has been informed to
the neighboring cell. If [allowed] is set or no value is set, in step F4,
cell selection processing unit 4004 adds the CSG ID of the neighboring
cell to the list of candidates for selection, on the other hand, if
[restricted] is set, in step F6, cell selection processing unit 4004 adds
the CSG ID of the neighboring cell to the restricted list.

[0140] The processing described above is performed for each of all
neighboring cells.

[0141] After the processing is completed for all the neighboring cells, in
step F7, cell selection processing unit 4004 extracts candidates for
manual CSG ID Selection from the list of candidates for selection and the
restricted list, and then, in step F8, displays on display 4007, the list
of candidates for manual CSG ID Selection. Note that the CSG ID that has
been removed from candidates for manual selection may not be displayed,
or may be displayed as a non-selectable CSG ID.

[0142] Here, the operation of UE 401 for extracting candidates for manual
selection will be described with reference to the flowchart shown in FIG.
12B.

[0143] Referring to FIG. 12B, in step G1, cell selection processing unit
4004 acquires a CSG ID from the list of candidates for selection, and in
step G2, sets the CSG ID as a candidate for manual selection.

[0144] In addition, in step G3, cell selection processing unit 4004
acquires a CSG ID from the restricted list, and in step G4, compares the
CSG ID with CSG IDs that has been included in the list of candidates for
selection.

[0145] If the CSG ID acquired from the restricted list is included in the
list of candidates for selection, in step G2, cell selection processing
unit 4004 sets the CSG ID as a candidate for manual selection.

[0146] Meanwhile, the CSG ID acquired from the restricted list is not
included in the list of candidates for selection, in step G5, cell
selection processing unit 4004 removes the CSG ID from candidates for
manual selection.

[0147] In addition, when one CSG ID is selected from candidates for manual
CSG ID Selection extracted through the above procedure, the UE selects
from among a plurality of cells assigned the CSG ID of interest, the cell
for which the parameter: Cell Prohibited for Manual CSG ID Selection is
set to [allowed].

[0148] As described above, in the present exemplary embodiment, in a
network environment in which the same CSG ID is assigned to a plurality
of femtocells, when the parameter: Cell Prohibited for Manual CSG ID
Selection of either of the femtocells is set to [allowed], even though
the parameter: Cell Prohibited for Manual CSG ID Selection of the other
femtocell is set to [restricted], UE 401 keeps the CSG ID as a candidate
for manual selection. When a suitable cell is selected from among the CSG
IDs selected through the manual selection procedure, the cell for which
the parameter: Cell Prohibited for Manual CSG ID Selection is set to
[allowed] is to be selected.

[0149] Therefore, an effect can be obtained in which candidates for manual
CSG ID Selection can be increased, and the UE can select the cell for
which the CSG ID is manually selectable.

Fourth Exemplary Embodiment

[0150] In the present exemplary embodiment, for each access class assigned
to the UE in advance, H(e)NBs 101 and 102 set a parameter indicating
whether the CSG ID included in System Information is manually selectable
by the UE. In this specification, this parameter is set for System
Information as Access Class Barred for Manual CSG ID Selection as shown
in FIG. 13.

[0151] In this case, UE 401 recognizes the value of the parameter of the
access class assigned to itself in advance, and based on the value,
determines whether the CSG ID is set as a candidate for manual selection.

[0152] As described above, in the present exemplary embodiment, not all
UE, but some UEs belonging to a specific access class can be prohibited
from manually selecting the CSG ID included in System Information that is
informed by the femtocell.

[0153] Therefore, an effect can be obtained inwhich a plurality of UEs
make a connection request by manual selection, thus the load control
processing of H(e)NBs 101 and 102 can be performed in stages.

Fifth Exemplary Embodiment

[0154] In the present exemplary embodiment, the present invention is
applied to the wireless communication system of an IMS (IP Multimedia
Subsystem)-Femto Architecture scheme.

[0155] FIG. 14 shows a configuration of the wireless communication system
of the present exemplary embodiment.

[0157] Note that in the present exemplary embodiment, compared to the
second exemplary embodiment of FIG. 3, only the architecture on the
network side is different, and messages exchanged between UE 400 and the
network are the same as those exchanged between UE 401 and H(e)NBs 101
and 102 in the second exemplary embodiment.

Sixth Exemplary Embodiment

[0158] The above exemplary embodiment is to prevent UE from selecting the
femtocell of the CSG to which the UE does not subscribe by manual
selection from a user who does not subscribe to the CSG.

[0159] However, the present exemplary embodiment is to introduce, in
operation of H(e)NB that operates in a Hybrid Access Mode, that is, in
operation of the H(e)NB that allows the UE of the user subscribing to the
CSG and the UE of the user not subscribing to the CSG to connect to the
femtocell, the similar parameter (Cell Prohibited for non CSG UEs) to
that of the second exemplary embodiment and the similar parameter (Access
Class Barred for non CSG UEs) to that of the fourth exemplary embodiment.

[0160] When the H(e)NB transmits the parameter to the femtocell or the UE,
all or some of the UEs used by users not subscribing to the CSG can be
prevented from accessing the femtocell for which the value of the
parameter is set to [restricted].

Seventh Exemplary Embodiment

[0161] In the above exemplary embodiment, the parameter is set for System
Information that is informed to the femtocell from the H(e)NB.

[0162] On the contrary, in the present exemplary embodiment, the above
parameters are set for another message that is to be transmitted from the
H(e)NB to the UE, such as an RRC Connection Setup message, a Cell Update
Confirm message, a UTRAN Mobility Information message and the like.

[0163] In this case, the UE can acquire the parameters along with the
message.

Eighth Exemplary Embodiment

[0164] In the above exemplary embodiment, a cell selected by the UE by the
manual selection from a user is the femtocell.

[0165] But, in the present exemplary embodiment, a cell selected by the UE
by manual selection from the user is the macro cell.

[0166] In this case, similar to the above exemplary embodiment, the
parameter may be set for System Information that is to be broadcast to
the macro cell, for example.

[0167] Note that the first to eighth exemplary embodiments have been
described by taking the wireless communication system such as femto and
IMS as an example. However, the present invention is not limited to these
systems, and may also be applied to other wireless communication systems
including a wireless communication terminal and a base station apparatus.

[0168] In addition, the method performed at UE 401 and H(e)NBs 101 and 102
according to the present invention may be applied to a program executed
by a computer. In addition, the program may be stored in a storage
medium, and provided outside through a network.

[0169] The present invention has been described concretely based on
preferred exemplary embodiments; however, needless to say, the present
invention is not limited thereto, and may be changed in various manners
without departing from the scope of the present invention.

[0170] The application claims the priority of Japanese Patent Application
No. 2009-105630, filed on Apr. 23, 2009, the entire of which is
incorporated herein by reference.